One mole of copper equals 6.02 × 10^23 atoms. The answer is letter C. This follows the
Avogaro’s law wherein 1 mole of a substance is equal to 6.02 x 10^23 atoms,
formula units or molecules. This is applicable to all substances.
Sodium. It reacts with most of every other element.
Answer:
3.
Explanation:
Hello,
In this case, it is convenient to write the chemical reaction as:

Which balanced turns out:

Thus the number that should be in front of the calcium sulfate is 3 in order to balance the reaction.
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Answer:
In strict SI units (highly recommended), express n in moles, R is the universal gas constant R=8.314Jmol−K , T is the temperature in Kelvins, and the volume V is in m3 . The resulting pressure P will be in Pa. R=0.082054L−atmmol−K , in which case the pressure is calculated in atm.
11. ionic charge +1, helium.
12. ionic charge 2-, neon.
13. ionic charge 3+, neon.